University of Edinburgh

Course: Visual Assessment of Children: The Orthoptist Role

Presented on Wednesday 9 February 2005

The Assessment and Treatment of Visual Perceptual Disorders in Dyslexia and Developmental Co-ordination Disorder

presented in February 2005

Nadia Northway PhD BA DBO SRO

Visual aspects of DCD and Dyslexia

  • Dyslexia and DCD are commonly found together therefore some overlap of visual problems
  • Low fusional reserves( compensates for ocular drift)
  • Low accommodation facility and amplitude ( focussing)
  • Poor convergence
  • Eye movement difficulties( saccades and SP)
  • Head commonly moves instead of eyes
  • Visual perceptual problems: visual figure ground, visual sequential memory, visual closure, visual memory, visual spatial relationships, form constancy

Meares-Irlen syndrome/Pattern Sensitivity

pattern sensitivity

Ocular Symptoms and Causes

  • Fatigue
  • Headaches
  • Diplopia
  • Blurring of print
  • Movement of print
  • Restlessness
  • Missing words and lines
  • Head Movement
  • Poor convergence, jump convergence
  • Strabismus or poor binocular vision (Squint)
  • Poor accommodation amplitude ( focussing)
  • Scanning/Tracking problems
  • Meares-Irlen syndrome
  • Saccadic problems
  • Attentional problems

Educational Symptoms and possible Causes

  • Poor copying : poor spatial memory and poor sequential memory, poor eye movement especially voluntary saccadic control, interference from inappropriate body movement
  • Poor writing:Immature motor skills, poor pencil grip, poor visual discrimination results in left right confusion, irregular size if MIS or other perceptual problems
  • Poor spacing of writing -Poor spatial vision and MIS, poor visual perception
  • Restlessness : Meares-Irlen syndrome, ocular discomfort, Sensory integration disorder
  • Poor Reading : Saccadic problems, ocular problems, MIS, poor visual memory, poor phonic ability
  • Poor Spelling : poor visual memory, poor phonics, poor visual sequential memory
  • Missing words and lines: poor eye movement, poor attention, poor visuo-spatial skills, poor tracking
  • Difficulty with written versus typed writing: If poor form constancy evident child may have difficulty with different presentations of writing e.g. handle , handle

Assessment Carried out at GCU

  • Orthoptic assessment
  • Overlays
  • Eye movement assessment
  • Visual discrimination test
  • VMI Beery Test ( recently acquired)
  • TVPS revised
  • Angels in the snow
  • Various physical tests such as hopping, finger sequencing
  • Sensory Profile questionnaire
  • Movement ABC screening questionnaire
  • Processing speed and other cognitive assessment if necessary

Intuitive Overlays

  • Perspex sheets with gloss and matt surface
  • 30 colour combinations possible
  • Assess reading speed with and without to determine prognosis
  • Time 15 minutes

Intuitive Colorimeter

  • Alters hue and saturation without changing luminance
  • Patient views crowded text.
  • Time 15-30 minutes
  • Depends on patient!

Testing eye movement

  • Use of eye tracker
  • Saccades: 3 positions
  • Anti-saccade using two pens
  • Reading speed
  • OKN
  • Developmental eye movement test

Developmental eye movement test

  • Compare horizontal and vertical scanning ability
  • Gives age related performance

In recent study 85% of children with DCD gave poor performance

Visuo-spatial difficulties/ Optic ataxia/ Simultaneous Perception

  • Leads to problems with copying and reading in classroom, loses place or takes long time to find next word or letter
  • Planning next movement difficult since do not have internal map
  • Child may not be able to chose where to look- problems with visually guided movement
  • Impaired simultaneous perception- if too much information available visually child cannot find relevant info

Orthoptic Therapy

  • Prescribe refractive error
  • Convergence treatment
  • Accommodation exercises using Tromboning, Dinosaur cards, Dot card, Flippers

Saccadic Training

  • Dot Card and Dinosaur Card
  • Saccadic Trainer
  • Physical Games
  • Computer aids such as Acereader

Scanning therapy

  • Scanning treatment
  • Letter searches
  • Word searches
  • Tracing
  • Tachistoscope
  • Computer programme such as ace readers
    scanning therapy

Other Therapies

  • Brain Gym
  • Sensory Integration Therapy
  • Multi-sensory learning
  • One to One teaching
  • Perceptual training , pegboards, flashcards, dominoes, playing cards, visual search tasks
  • Occupational therapy

Visuospatial memory strategies

  • Position in classroom
  • Positioning of copy material
  • Games practice
  • Search games
  • Jigsaws etc
  • Happy Families


  • Assessment by orthoptist
  • Consider spacing of text and font used- enlarge
  • Scanning exercises or eye movement exercises
  • Overlays
  • Orthoptic treatment
  • Break up reading tasks
  • Computer -change background, font etc
  • Change paper colour or sheen
  • Position in classroom and books
  • Tachistoscope


  • Visual problems are part of dyslexia and DCD but many are treatable.
  • Improvement in visual function can help teacher facilitate academic improvement.
  • Many treatment options may be necessary to improve classroom function.
  • Problems of print size etc and issues with visually impairment support.

Visual Assessment of Children: The Orthoptist Role